I apologize if any of this is misspelt I'm attempting to write this on my phone.  

In the Manga I noticed that Haruka seems to be really drawn towards Usagi. My question is what causes it? Is it simply because she thinks Usagi is cute? Does she subconsciously know Usagi is her Princess? Or could she possibly just be drawn to the crystal?

What do you guys think?

She does it because of lesbianism.

In all seriousness, I personally think it starts as teasing and then ends as longing and love, though not in the romantic sense, just in the same love that pretty much everyone has for Usagi in the manga. Takeuchi didn't make Haruka and Michiru's relationship all that solid in the manga. In fact, it's almost just homoerotic. I think Takeuchi was merely adding the romantic tension for homo-eroticism and overall tension.

I always thought in the manga that both Neptune and Uranus knew of Usagi and Mamoru's identities even when they first meet. Cause Michiru is also a bit into Mamoru as well, while Haruka is shown doing more to Usagi than we see Mihciru to Mamoru. It probably has partly to do with adding to the overall tension and drama as CJ points out, but also I think her love for her as her Princess.

I think another thing may have to do with how Naoko based Haruka and Michie off Takarazuka actresses. I think Haruka is meant to be like the actress thats the cool, masculine, flirty type as well (Look at Yamato Yuuga lol). So there is probably that too as part of why Naoko played it out the way she did.

Small Lady wrote:

I always thought in the manga that both Neptune and Uranus knew of Usagi and Mamoru's identities even when they first meet. Cause Michiru is also a bit into Mamoru as well, while Haruka is shown doing more to Usagi than we see Mihciru to Mamoru. It probably has partly to do with adding to the overall tension and drama as CJ points out, but also I think her love for her as her Princess.

I think another thing may have to do with how Naoko based Haruka and Michie off Takarazuka actresses. I think Haruka is meant to be like the actress thats the cool, masculine, flirty type as well (Look at Yamato Yuuga lol). So there is probably that too as part of why Naoko played it out the way she did.

^This. Also, Haruka is a giant flirt. In the 90's anime she flirts with Makoto and the others here and there. She seems to enjoy making Michiru "jealous" (in quotations because Michiru never really seems to mind and in fact, I would say, thinks it's very cute and an endearing part of Haruka's personality) too. I think, and this is entirely speculation, but Haruka probably also enjoys the way Usagi's personality plays off of hers. Usagi takes things so literally and gets so confused, I can really see that Haruka would enjoy that to the fullest.

Because Usagi is the Princess and The Girl so everybody loves her. All the senshi adores her, but you gotta admit Seiya and Haruka kinda taking it to another level. Mamo is Mamo so I'm not including him here.

I just never found the whole Haruka-Usagi thing amusing -especially since I'm a diehard Harumichi shipper- and sometimes I feel like Haruka is emotionally cheating on Michiru. Frankly I'm dreading how Crystal would animate that. However, I also never found Michiru as being attracted to Mamoru either since I always see it as her way trying to get close to him for senshi purposes. It's also Naoko's plot device to make Usagi jealous but I digress.

Sailor CJ wrote:

She does it because of lesbianism.

In all seriousness, I personally think it starts as teasing and then ends as longing and love, though not in the romantic sense, just in the same love that pretty much everyone has for Usagi in the manga. Takeuchi didn't make Haruka and Michiru's relationship all that solid in the manga. In fact, it's almost just homoerotic. I think Takeuchi was merely adding the romantic tension for homo-eroticism and overall tension.

I think that Haruka and Usagi have a very interesting relationship that is different than the relationship that Usagi has with her inner senshi and with the other three outer senshi. I feel like they have more like a Knight and Queen type of relationship like you see in the tales of King Arthur. I've gotten the impression from the anime and manga that Usagi would confide things in Haruka that she couldn't tell the inners and wouldn't feel comfortable telling Michiru or Setsuna. I find it to be a very interesting dynamic. 

Small Lady wrote:

I always thought in the manga that both Neptune and Uranus knew of Usagi and Mamoru's identities even when they first meet. Cause Michiru is also a bit into Mamoru as well, while Haruka is shown doing more to Usagi than we see Mihciru to Mamoru. It probably has partly to do with adding to the overall tension and drama as CJ points out, but also I think her love for her as her Princess.

I think another thing may have to do with how Naoko based Haruka and Michie off Takarazuka actresses. I think Haruka is meant to be like the actress thats the cool, masculine, flirty type as well (Look at Yamato Yuuga lol). So there is probably that too as part of why Naoko played it out the way she did.

I did find that really interesting that they knew. I wonder if they found out through detective work or if they woke up knowing that Usagi was the Princess and Mamoru was the Prince. How did they know they would be Queen one day? Unless with the changes that happened in the Black Moon Arc granted them those memories. 

It did add tension for Usagi and she did become confused. We don't really see much of Mamoru's point of how he's feeling about Michiru.

For me, it's both the fact that she is a lesbian and Usagi does resemble the the "Princess".  Or could be that she just darn attracted to how cute Usagi is.